Download Insertion of medial collateral ligament of the elbow joint in adult

Animal Microscopic Anatomy
Insertion of medial collateral ligament of the
elbow joint in adult mongrel dogs
Santos, JML., Oliveira, D., Moraes, MFD., Lacerda, TB. and Barbosa, AMS.
Unidade Acadêmica de Garanhuns/UFRPE
Introduction: The medial collateral ligament (MCL) in dogs has the main function of preventing excessive or abnormal
movement and maintaining the stability of the elbow joint. Proximal insertion is situated deep in the carporadial flexor muscle, attaching to the medial epicondyle of the humerus. Distal insertion of the MCL extends distally beginning at the distal
cranial portion of the epicondyle, attaching to the medial proximal region of the radius. The reconstruction of the MCL has
proven to be insufficient when using synthetic materials. Due to the scarcity of literature, it is necessary to study the insertion
of the medial collateral ligament of the elbow of adult dogs, determining the arrangement of collagen fibers and cell types.
Methods and results: Four elbow joints were used from four mongrel dogs over one year of age. The medial epicondyle of the
humerus and the proximal epiphysis of the radius were sawn and the fragments, together with the medial collateral ligaments
at their points of attachment, were immersed in Bouin solution. Histological sections were then stained with HematoylinEosin and the slides were analyzed and photodocumented with a digital camera coupled to an optical microscope. At the
proximal insertion in the transition regions between the bone and ligament, the presence of collagen fibers set perpendicular
to the bone was found in a greater quantity than at the distal insertion. Between the insertions, there were fibroblasts and
chondrocytes, which are characteristic of fibrocartilage. At the distal insertion of the MCL, a large amount of fibroblasts were
observed, along with the presence of collagen fibers in a discontinuous manner in relation to the proximal insertion. In both
insertions, the fibrocartilage in the bone-ligament junction gradually blended with thick collagen of the periosteum and only
spanned a short distance into the external layers of the cortex. Conclusion: Medial collateral ligament insertions are made
up of tissues that are responsible for facilitating movements between the bones, offering resistance to tension and protecting
the elbow joint.
Braz. J. Morphol. Sci., 2008, vol. 25, no. 1-4, p. 35-108
73